Guideway for machine tools



July 16; 1929. A. M; DRAKE 1,721,009

GUIDEWAY FOR MACHINE TOOLS Filed Aug. 6. 1926 Patented July 16, 1929.

warren stares PATENT orrics.

ALDEN M. DRAKE, OF G'REENFIELD, MASSACHUSETTS, ASSIGNOE TO GREENFIELI) TAP AND DIE CORJPORATION, OF GREENFIELD, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

Application filed August 6, 1926.

This invention relates to guideways which support a horizontally reciprocating member on a machine tool. Such reciprocating members are in common use as work tables or tool supports on many different machine tools, such as grinding machines, planers, lat-hes, screw-machines, and the like.

It is the object of my present invention to providev an improved type of guideway for a horizontally reciprocating member in a machine tool, by which the tool pressure applied to said member may be more effectively counteracted, and by which the tab-lo will be caused to move more steadily and uniformly and to rest more firmly upon the machine frame. a v

To the attainment of this object I have provided the preferred construction shown in the drawing, which is a transverse sectional elevation of parts of an internal grinding machine having by invention applied thereto.

While I have shown the invention as embodied in a grinding machine, it is ofgeneral application and the indication of parts of an internal grinding machine is illustrative only and in no way limits the invention thereto.

Referring to the drawing, I have indicated a-bed or frame 10, a horizontally reciproeating member 11, and a work holder 12 secured to said member 11. The work K is secured to the work-holder by any suitable means, such as clamping jaws 13, and the work-holder is rotated in any convenient manner. A grinding wheel is indicated at W and operates against a rear portion of the internal cylindrical surface of the work K. All of these parts are of the usual construction and in themselves form no specific part of my present invention, which relates specially to the guideways upon which the reciprocating member 11 is mounted and supported.

I have shown the member 11 as supported upon two parallel guideways, the front guideway 15 comprising simply a straight, flat, horizontal surface on the frame 10 engaged by a similar surface on the member 11. This guideway 15 has no function in guiding the member 11 transversely, but simply supports the front portion of the member 11 for movement in a horizontal plane.

Serial No. 127,688.

The rear guideway 16, however, is of special construction and is preferably of a substantially V shape, but with the front wall 18 and the rear wall 20 disposed at unequal angles to a vertical line as a.

vl hile these angles may be varied somewhat in practice, I have indicated a satisfactory construction in the drawing, in which the front wall 18 of the guideway is inclined forwardly at an angle of substantially degrees to the vertical line a, while the rear wall 520 is inclined rearwardly at. an angle of substantially degrees to the line a. The front and rear walls 18 and 20 thus form an angle of about degrees with each other.

Reference to the drawings will indicate that the rear face 20 of the guideway 16 is disposed at a forwardly displaced and slightly obtuse angle F) with respect to a line joining the point of contact of the wheel and work with the face 20 instead of being at an acute angle thereto as is the usual practice. With this obtuse position of the engaging surfaces, the pressure of the whee tends to seat the member 11 more firmly in its guideways, with a sort of wedging action, instead of tending to raise or push the member 11 out of its guideways, by the rearward pressure as wit-h the usual V-shaped guideways having equal angles.

I have found in practice that this provision of unequally disposed faces for the V- shaped guideway gives very important ad vantages, as the reciprocating member re mains at all times firmly seated on the guideways and the tendency to lift under heavy pressure is entirely eliminated.

l Vith the use of my improved guideways, it is entirely unnecessary to provide gibs, clamps or presser rolls or any other construction to hold the member 11 seated upon the frame 10, as there is no tendency for the member to lift off of the frame under any operating conditions.

Having this described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed otherwise than as set forth in the claims, but what I claim is 1. In a machine tool, a reciprocating member, and a frame supporting said member, said frame and member having parallel horizontally extending guideways thereon,

one of said guideways in said frame forming an upwardly open longitudinal groove substantially V-shaped in cross section, with the rear side surface thereof forming an angle of substantially degrees rearward from the vertical. and the front side surface forming an angle of substantially 60 degrees forward from the vertical, and said reciprocating member having adepending guiding portion of similar cross section co-operating therewith.

2. In a machine tool, a reciprocating member, and a frame supporting said member, said frame and member having parallel hori- "ally extending guideways thereon, one of d guideways in said frame forming an Sit upwardly open longitudinal groove substantially J-sb ped in cross section, with the sides of id guii'leways forming an angle of appro iatcly 90 degrees with each other but the rearward face of said guidewaybeing placed at a substantially less angle with the vertical than the front face, and said reciprocating member havin a depending guiding portion of similar cross section cooperating therewith.

8. In a machine tool, a reciprocating member, and a frame supporting said member, said frame and member having parallel horizontally extending guideways thereon, one of said guideways in said frame forming an upwardly open longitudinal groove sub stantially V-shapeo in cross section with its rear face forming a slightly obtuse angle with a line joining said rear face to the point of operative contact of the tool and work, and said reciprocating member having a depending guiding portion of similar cross section cooperating therewith, whereby the tool pressure is rendered effective to firmly seat said reciprocating member in said guideway.

4. In a machine tool, a reciprocating memher, and a frame supporting said member, said frame and member having parallel horizontally extending guideways thereon, one of said guideways in said frame forming an upwardly open longitudinal groove substantially \!-shaped in cross section with its rear face forming a slightly obtuse angle with a line joining said rear face to the point of operative contact of the tool and work, and with its forward face approximately perpendicular to the rear face, and said reciprocating member having a depending guiding portion of similar cross section cooperating therewith, whereby the tool pressure is rendered effective to firmly seat said reciprocating member in said guideway.

5. In a machine tool, a reciprocating member and a frame supporting said member, said frame and member having one flat horizontal guide-waytherebetween and having a second guide-way extending alongside and parallel. to said first guideway, and having the guiding portion thereof on said frame forming an upwardly open longitudinal groove substantially V-shaped in cross section with its sides forming unequal angles with the vertical, and the portion of said second guide-way on said reciprocating memher having a depending guiding portion of similar cross section seated in said groove and co-operating therewith.

In testimony whereof I have hereunto affixed my signature.

ALDEN M. DRAKE. 

